Hair transplantation procedures are well-known, and typically involve harvesting donor hair grafts from one area of the body (“donor areas”), and implanting them in another area (“recipient area”). Various procedures and instruments for hair transplantation have been developed and disclosed, including both manual and mechanized processes and instruments to certain degrees of automation. In one well-known process, a linear portion of the scalp is removed from a donor area by dissection, using a scalpel to cut down into the fatty subcutaneous tissue. The strip is then dissected (under a microscope) into the component follicular units, which are then implanted into a recipient area in respective puncture holes made by a needle. Forceps are typically used to grasp and place the follicular unit grafts into the needle puncture locations, although other instruments and methods are known for doing so.
Automated (e.g. robotic) systems and methods for harvesting and implanting hair follicular units have been invented and are currently under commercial development. By way of example, U.S. Pat. No. 6,585,746 to Gildenberg discloses a hair transplantation system utilizing a robotic system, including a robotic arm and a hair follicle introducer associated with the robotic arm.
By way of further examples, U.S. patent application Ser. No. 11/380,903, published as U.S. patent publication 20070078466, and Ser. No 11/421,438, published as U.S. patent publication 20070078475, (both assigned to the assignee of the present application), disclose and describe automated systems for transplanting hair follicular units which employ a multi-part tool assembly carried by a robotic arm. The tool assembly includes an inner, “harvesting” cannula and an outer, “implanting” cannula disposed coaxially over (and moveable relative to) the harvesting cannula. U.S. patent application Ser. Nos. 11/380,903 and 11,421,438 are hereby incorporated by reference for all that they disclose.